import sympy as sp

x = sp.symbols('x')  # 定义符号变量
f = (2*0.0015*x - 2*0.00075)  # 定义被积函数
integral = sp.integrate(f, x)  # 计算不定积分
print("integral 1st:", integral)  # 输出：0.0015*x**2 - 0.0015*x

f = 0.0015*x**2 - 0.0015*x
integral = sp.integrate(f, x)  # 计算不定积分
print("integral 2nd:", integral)  # 输出：0.0015*x**2 - 0.0015*x

